Collapsible support

ABSTRACT

A support structure has a folding leg movement based upon a &#39;&#39;&#39;&#39;scissors&#39;&#39;&#39;&#39; mechanism, one section of which is pivoted to a support frame, and the other section to a link member also connected to the frame. A diagonal latch locks the extended position of the structure by fixing the position of the junction between the link and the latter leg section. A tension spring neutralizes the weight of the structure by interconnecting the upper extremities of the &#39;&#39;&#39;&#39;scissors&#39;&#39;&#39;&#39; configuration. This spring is also used as a guide for the diagonal latch. The folded position of the structure is secured by interengaging a part of the leg system with the frame so that the unit can be stored vertically. Full wheel support is provided in the folded position, and partial wheel support in the extended position.

United States Patent [191 Cook [ COLLAPSIBLE SUPPORT [75] Inventor: Gregory Edward Cook Chicago, Ill.

[73] Assignees: Harold .1. Baer; Harold J. Baer. Jr.;

Lawrence J. Baer, all of Grand Rapids, Mich.

122] Filed: Jan. 10, 1974 121] App]. No.: 432,417

3,752,527 8/1973 Ferneau et al 108/120 Aug. 5, 1975 Primary Examiner-James C. Mitchell Attorney, Agent. or Firm-Glenn B. Morse [57] ABSTRACT A support structure has a folding leg movement based upon a scissors" mechanism, one section of which is pivoted to a support frame, and the other section to a link member also connected to the frame. A diagonal latch locks the extended position of the structure by fixing the position of the junction between the link and the latter leg section. A tension spring neutralizes the weight of the structure by interconnecting the upper extremities of the scissors" configuration. This spring is also used as a guide for the diagonal latch. The folded position of the structure is secured by interengaging a part of the leg system with the frame so that the unit can be stored vertically. Full wheel support is provided in the folded position. and partial wheel support in the extended position.

7 Claims. 11 Drawing Figures PATENTED AUG 5 I975 SHEET COLLAPSIBLE SUPPORT BACKGROUND OF THE INVENTION Supporting structures with folding leg systems are common, appearing in a wide range of items from card tables to ironing boards. One type of mechanism frequently used in these structures involves a so-called scissors" configuration, in which a pair of leg elements intersect at a pivot connection centrally along their length. This produces an X shape in the extended position, which folds into a position in which both leg sections are essentially co-planarv The lower extremities of these leg sections will normally bear directly against the floor, or are provided with wheels. It is obvious that an approaching and separating motion be tween the upper portions of the scissors system must be accommodated at the connection between the leg sections and whatever supporting frame may be carried by these leg sections. The usual practice is to pivot one of the leg sections directly to the frame, with the upper extremity of the opposite leg section having some form of sliding engagement. A less-frequently used arrangement involves the interconnection of the upper extremity of the latter leg section to the supporting frame by a link.

The scissors mechanism is commonly biased to an extended position by the use ofa tension spring extending between portions of the leg sections that are remote from their pivotal interconnection. This arrangement is sometimes seen in the hinge mechanisms for automobile hoods. The principles of the biased scissors mechanism have been incorporated in the present invention. For a variety of purposes, it is as advantageous to have a weight-neutralized folding movement of the leg system combined with a positive and readily excessible latching mechanism controlling at least the extended position of the leg system. For the type of articles in which these features are most useful, cost is always a paramount factor. The invention is thus directed at the incorporation of the general principles outlined above in a structure having a minimum of moving parts and complexity, relatively wide manufacturing tolerances, and simple assemblyv SUMMARY OF THE INVENTION A scissors" leg system has one leg section pivotally connected to a supporting frame, with the other leg section pivotally connected to a link which is also connected to the supporting frame. The relative proportions of these components are such that the supporting frame retains an essentially horizontal position as the structure moves from erect to folded condition. At least one tension spring extends from the junction of the link with the second leg section preferably across to the shaft providing the pivotal connection of the first leg section to the frame. The extension of the spring takes place at the same time as a decrease in leverage of the spring, which results in a fair approach to neutralizing the weight of the supporting frame during the full movement from folded to erect condition. The tension spring is also used as a guide for a diagonal latch preferably extending from the same shaft providing the spring connection. The latch is engageable at selected positions with the shaft preferably providing the pivotal connection between the second leg section and the link. Semi-wheeled support in the extended position is provided by mounting wheels at the lower extremity of one of the leg sections, and full wheeled support in the folded position is provided by additionally mounting wheels on the shaft pivotally connecting the first leg section to the frame. All four wheels are adapted to provide floor engagement in the folded position of the structure. The folded position is also secured by interengaging a portion of the leg structure with a member fixed with respect to the handle, in order to block the natural tendency for the leg system to extend upon applying a lifting action to any part of the frame.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a device embodying the present invention adapted to support a saddle and its associated equipment.

FIG. 2 is a perspective view of the unit shown in FIG. I from the opposite end.

FIG. 3 is a perspective view showing the collapsed condition of the structure shown extended in FIGS. 1 and 2.

FIG. 4 is a perspective view of the structure in the condition of FIG. 3, but standing on end for certain types of storage.

FIG. Sis a perspective view of the unit in the FIG. 3 position, from the opposite end.

FIG. 6 is a view similar to FIGv 4, showing the opposite side of the unit.

FIG. 7 is a perspective view of the structure in the erect condition, with the saddle-supporting panel removed.

FIG. 8 is a perspective view similar to FIG. 7, from the opposite end.

FIG. 9 is a fragmentary perspective of the structure shown in FIGS. 7 and 8, on an enlarged scale.

FIG. 10 (see sheet 2) is a perspective view taken primarily at the side of the structure, showing an intermediate position in the folding movement.

FIG. ll is a perspective view similar to that of FIG. 10, showing the fully erected condition of the structure.

DESCRIPTION OF THE PREFERRED EMBODIMENT The structure shown in the drawings is adapted to support a saddle by the addition of the molded panel 20 to a supporting frame which includes the central tube 21 terminating in the handle portion 22, together with the transverse members 23 and 24, The panel 20 is preferably attached to this frame at the slanted shoulder areas 25-26 and 27-28 by screws or any other convenient fastenings (not shown). The stop 29 is added merely as a means of determining the desired position of the saddle on the structure for best balance.

The first leg section 30 is composed of the leg elements 31 and 32 on the opposite sides of the device, interconnected by the cross member 33 at the lower extremity. The elements 31 and 32 are pivotally connected to the frame member 24 by the shaft 34. Wheels 35 and 36 are mounted near the lower extremity of the leg elements 31 and 32.

A second leg section 37 is composed of the leg elements 38 and 39 on the opposite sides of the unit, interconnected by the cross member 40. The leg sections 30 and 37 are pivotally interconnected at a point intermediate along their length by the rod 41. The rod 43 provides a pivotal interconnection between the upper extremities of the leg elements 38 and 39 of the leg section 37 to the links 44 and 45. The upper extremities of these links are pivotally connected to the frame member 23 by the rod 46. The cross member 47 interconnects the links 44 and 45 at a position spaced from the pivot rod 43, and the opposite ends of the member 47 extend laterally outward sufficiently to bear against the leg elements 38 and 39 to provide a stop limiting the articulation of the links with respect to the leg section 37 at a point where these components are essentially co-planar.

The disengageable diagonal brace 48 is provided to lock the erect position of the structure shown in FIGS. 1 and 2. The laterally opposite latch arms 49 and 50 are interconnected by the transverse portion 42 to form a U shaped Configuration, and are pivotally mounted on the shaft 34. The latch arms are also interconnected by the cross members SI and 52. The tension springs 55 and 56 extend from the shaft 34 to the rod 43, and pass between the cross members and 52. The springs therefore function as a guide establishing the position of the latch when it is not bearing on the rod 43. The erect position of the structure is determined by the interengagement of the notches 53 and 54 with the rod 43 at various positions to provide adjustable height to the erected structure. During the movement of the structure to the erected position, the springs 55 and 56 guide the diagonal latch toward the rod 43, cause it to slide over the top of it until the notches 53 and 54 can engage the rod, and also provide a gentle biasing action tending to pull the latches down into engagement with the rod 43. Since the springs 55 and 56 are merely hooked over the rods 34 and 43, it is desirable to incorporate lateral abutments as shown at 57 and 58 (note FIG. 9) on the cross member 52 a of the diagonal latch to prevent the springs from working out of their pre ferred position.

In the folded position of the structure shown in FIG. 3, the provision of the small wheels 59 and 60 on the shaft 34 combine with the effect of the wheels 35 and 36 to provide a four-wheel floor support for the device in this condition. The diameter of the wheels 59 and 60 is selected to be sufficient to provide clearance for the fixed portions of the adjacent structure. The offsets in the leg elements 31 and 32 near the lower extremity, and the position of the axes of the wheels 35 and 36 on these offsets, results in supporting that end of the structure at a position such that the folded condition appears generally horizontal, even though the wheels 35 and 36 are of much greater diameter than the wheels 59 and 60. It is often desirable to pick up the device in the folded condition, and perhaps place it in a closet or in some other area where it is desirable to store it on end as shown in FIG. 6. The handle 22 forms a natural point at which to grasp the device; but unless special provision is made, any attempt to merely lift the handle will result in bringing the device up to the erect position shown in FIGS. l and 2. This tendency can be prevented to facilitate the FIG. 6 type of storage by the ad dition of the retainer 61, which is essentially a loop of small-diameter rod with the ends formed into small loops to provide a pivotal attachment to the rod 33. The dimensions of these components are such that the retainer 61 may be swung from the FIG. 2 position to that shown in FIG. 3, pulling it up over the end of the handle 22. It is not necessary that the handle 22 be held 6 ficient clearance for the engagement and disengagement. The end of the handle 22 is preferably within approximately an inch of the rod 33. With the retainer 61 engaged as shown in FIG. 3, the device may be picked 5 up easily by the handle, with the effect of the retainer 61 being to prevent extension of the leg system so that the device can be installed in any storage space in the position shown in FIG. 6.

Disengagement of the diagonal latch 48 by pulling it upward slightly through grasping the cross member 52 will permit the device to be lowered through the application of very gentle forces to the handle 22, as a result of the weight-neutralizing effect of the springs 55 and 56. This disengagement will also permit a degree of height adjustment through utilizing the various notches 53 and 54. It should be noted that the generally coplanar relationship of the links 44-45 and the leg elements 3839 corresponds to the notches at the left extremity of the group shown in FIG. 10. Use of the other notches will permit a degree of buckling between the links 44 and 45 and the leg elements 3839 in the direc tion shown in FIG. 10, and will correspondingly reduce the height of the structure. This height adjustment may be utilized for a variety of purposes, depending upon the particular function for which the unit is adapted.

When used as a saddle support, the height adjustment will normally not be required. If the unit is to function as a work-supporting surface, the height adjustment may be very useful. When the unit is adapted as a saddle carrier, the addition of the hook 62 is useful as a point for the suspension of some of the various trappings and associated equipment normally used in con junction with a saddle.

I claim:

1. A collapsible support including a frame and folding leg means mounted for articulation with respect to said support frame, wherein the improvement comprises:

a first section of said leg means, said first section being pivotally connected at the normally upper extremity thereof to said frame;

a second section of said leg means, said second section being pivotally connected to said first section at an intermediate point thereon;

link means pivotally connected at one end to the normally upper extremity of said second section, the opposite end of said link means being pivotally connected to said frame at a point thereon remote from the connection of said first section thereto;

and

latch means operable to disengageably fix the angle of intersection of said first and second sections with respect to each other, said latch means being pivotally connected to said frame coaxially with the pivotal connection of said first leg section to said supporting frame.

2. A collapsible support including a frame and folding leg means mounted for articulation with respect to said support frame, wherein the improvement comprises:

a first section of said leg means, said first section being pivotally connected at the normally upper extremity thereof to said frame;

a second section of said leg means, said second section being pivotally connected to said first section at an intermediate point thereon;

link means pivotally connected at one end to the normally upper extremity of said second section, the opposite end of said link means being pivotally connected to said frame at a point thereon remote from the connection of said first section thereto; and

latch means operable to disengageably fix the angle of intersection of said first and second sections with respect to each other, said second leg section and link means being pivotally connected by a rod, and said latch means is engageable with said rod to lock the extended position of said leg means.

3. A collapsible support including a frame and folding leg means mounted for articulation with respect to said support frame, wherein the improvement comprises:

a first section of said leg means, said first section being pivotally connected at the normally upper extremity thereof to said frame;

a second section of said leg means, said second section being pivotally connected to said first section at an intermediate point thereon;

link means pivotally connected at one end to the normally upper extremity of said second section, the opposite end of said link means being pivotally connected to said frame at a point thereon remote from the connection of said first section thereto;

latch means operable to disengageably fix the angle of intersection of said first and second sections with respect to each other; and

a tension spring urging the upper extremities of said leg sections toward each other, said latch means including members adapted to bear on the normally upper and lower sides of said tension spring to guide said latch means.

4. A support as defined in claim 3, wherein said first leg section is pivotally connected to said frame by a shaft, and said second leg section and link means are interconnected by a rod, and said tension spring extends from said shaft to said rod, said latch means being mounted on said shaft.

5. A support as defined in claim 3, additionally in cluding retaining means engageable with said frame and a member secured to said leg means exclusively in the folded position of said leg means to maintain said folded position.

6. A support as defined in claim 5, wherein said frame includes a central handle portion, and one of said leg sections has a cross member adjacent to the lower extremity thereof, said retaining means being operable to secure said cross member to said handle portion.

7. A support as defined in claim I, wherein said first leg section is pivotally connected to said frame by a shaft, and further including wheel means mounted on said shaft and adapted to partially support said collapsible support in the folded condition of said leg means. 4 i l 

1. A collapsible support including a frame and folding leg means mounted for articulation with respect to said support frame, wherein the improvement comprises: a first section of said leg means, said first section being pivotally connected at the normally upper extremity thereof to said frame; a second section of said leg means, said second section being pivotally connected to said first section at an intermediate point thereon; link means pivotally connected at one end to the normally upper extremity of said second section, the opposite end of said link means being pivotally connected to said frame at a point thereon remote from the connection of said first section thereto; and latch means operable to disengageably fix the angle of intersection of said first and second sections with respect to each other, said latch means being pivotally connected to said frame coaxially with the pivotal connection of said first leg section to said supporting frame.
 2. A collapsible support including a frame and folding leg means mounted for articulation with respect to said support frame, wherein the improvement comprises: a first section of said leg means, said first section being pivotally connected at the normally upper extremity thereof to said frame; a second section of said leg means, said second section being pivotally connected to said first section at an intermediate point thereon; link means pivotally connected at one end to the normally upper extremity of said second section, the opposite end of said link means being pivotally connected to said frame at a point thereon remote from the connection of said first section thereto; and latch means operable to disengageably fix the angle of intersection of said first and second sections with respect to each other, said second leg section and link means being pivotally connected by a rod, and said latch means is engageable with said rod to lock the extended position of said leg means.
 3. A collapsible support including a frame and folding leg means mounted for articulation with respect to said support frame, wherein the improvement comprises: a first section of said leg means, said first section being pivotally connected at the normally upper extremity thereof to said frame; a second section of said leg means, said second section being pivotally connected to said first section at an intermediate point thereon; link means pivotally connected at one end to the normally upper extremity of said second section, the opposite end of said link means being pivotally connected to said frame at a point thereon remote from the connection of said first section thereto; latch means operable to disengageably fix the angle of intersection of said first and second sections with respect to each other; and a tension spring urging the upper extremities of said leg sections toward each other, said latch means including members adapted to bear on the normally upper and lower sides of said tension spring to guide said latch means.
 4. A support as defined in claim 3, wherein said first leg section is pivotally connected to said frame by a shaft, and said second leg section and link means are interconnected by a rod, and said tension spring extends from said shaft to said rod, said latch means being mounted on said shaft.
 5. A support as defined in claim 3, additionally including retaining means engageable with said frame and a member secured to said leg means exclusively in the folded position of said leg means to maintain said folded position.
 6. A support as defined in claim 5, wherein said frame includes a central handle portion, and one of said leg sections has a cross member adjacent to the lower extremity thereof, said retaining means being operable to secure said cross member to said handle portion.
 7. A support as defined in claim 1, wherein said first leg section is pivotally connected to said frame by a shaft, and further including wheel means mounted on said shaft and adapted to partially support said collapsible support in the folded condition of said leg means. 